Clinical and demographic factors associated with delayed diagnosis of bipolar disorder: Data from Health Outcomes and Patient Evaluations in Bipolar Disorder (HOPE-BD) study

•There was an 8-year gap between the onset and diagnosis of bipolar disorder•Diagnostic delay was longer in bipolar disorder type II compared to type I•Diagnosis took longer in childhood-onset compared to adult-onset bipolar disorder•Lifetime suicide attempts and anxiety disorders were correlated with a longer delay•Lifetime psychotic symptoms and hospitalizations were linked to a shorter delay The diagnosis of Bipolar Disorder (BD) is frequently delayed. In this study, we aimed to examine the clinical and demographic factors associated with delayed diagnosis of BD, defined as the difference between the age at first mood episode (depressive, manic, or hypomanic) and the age at the correct diagnosis of BD, using data from a Canadian multicentre naturalistic study. The sample included 192 patients with Bipolar I Disorder (BD-I) and 127 with Bipolar II Disorder (BP-II) who participated in the Health Outcomes and Patient Evaluations in Bipolar Disorder (HOPE-BD) study. Sociodemographic characteristics and clinical features that had been previously associated with delayed diagnosis of BD were included in the analysis. The median delay in diagnosis was 5.0 years in BD-I and 11.0 years in BD-II. Clinical factors such as earlier age of onset, lifetime suicide attempts and comorbid anxiety disorders were associated with a longer delay, whereas the presence of lifetime psychotic symptoms and psychiatric hospitalizations were associated with a shorter delay. Quantile regression analysis showed older age at which professional help was first sought and younger age of onset as predictors of increased delay in diagnosis of BD-I and BD-II. Depression as first episode predicted longer delay in diagnosis of BD-I but not BD-II. Our findings identified the ongoing lag in identification of a BD diagnosis and the clinical markers most associated with this delay, highlighting the need for implementation of strategies for early identification and interventions in BD.